Honing tool having spring mounted abrasive elements



M. A. MAGSIG 3,195,282

July 20, 1965 HONING TOOL HAVING SPRING'MOUNTED ABRASIVE ELEMENTS Filed July 15, 1963 2 Sheets-Sheet 1 INVENTOR.

A M/v4 r A. 4446676 4 mm m )MMQW HONING TOOL HAVING SPRING MOUNTED ABRASIVE ELEMENTS M. A. MAGSIG July 20, 1965 2 Sheets-She et 2 Filed July 15, 1963 INVENTOR. MAMZ) A. 141146676 BY MM, Mk W ATTOR/VIYS United States Patent HONING TOOL HAVING SPRING MOUNTED ABRASIVE ELEMENTS Manly A. Magsig, Owosso, Mich, assignor to Midwest Abrasive Company, Owosso, Micln, a corporation of Delaware Filed July 15, 1963, Ser. No. 295,096 3 Claims. (Cl. 51-346) This invention relates generally to a honing tool and refers more particularly to a honing tool of the type having expandable honing elements retained in slots in the hone body.

One object of the invention is to provide a honing tool having a spring member in a slot of the hone body which frictionally retains the honing element in place.

Another object is to provide a honing tool having an elongated honing element in the slot, and a spring member lining at least a portion of the slot and resiliently and friction-ally engaging the honing element to retain it in place.

Another object is to provide a flexible resilient leaf spring lining at least a portion of the slot and having a free end portion resiliently and frictionally engaging the honing element.

Another object is to provide an elongated flexible resilient leaf spring secured in and lining the major portion of the slot, the spring having a free end portion which normally extends inward away from the slot wall but which is flexed outward by the honing element when the latter is in the slot so as to frictionally engage the honing element and retain it in place.

Another object is to provide a liner for the slot or slots of worn honing tools. The slots can be reground to accommodate the liners at low cost, and the liners are preferably of a spring material to frictioually retain the honing elements.

Other objects and features of the invention will become apparent as the description proceeds, especially when taken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a longitudinal sectional view of a honing tool embodying my invention.

FIGURE 2 is a fragmentary perspective view of the honing tool shown in FIGURE 1, illustrating the leaf spring liner with its end portion in the free state extending inward with respect to the slot, and also showing a honing element about to be inserted.

FIGURE 3 is similar to FIGURE 2 but shows the honing element inserted and the end portion of the spring liner flexed outward by the honing element and in frictional contact therewith.

FIGURE 4 is a sectional view taken on the line 44 of FIGURE 1.

FIGURES 5 and 6 are similar to FIGURES 2 and 3, respectively, but show a modification.

Referring now more particularly to the drawings and especially to FIGURES 1-4, there is illustrated a honing tool 10 having a hollow head or body 12. The body 12 has an enlarged cylindrical portion 14 which is formed with a plurality of elongated axially extending circumferentially spaced slots 16. These slots extend through to the hollow interior of the hone body, and each has the straight parallel side walls 18 and the curved end walls 20. One side 18 of each slot has a recess 19 therein. Elongated honing elements, generally designated 22, are disposed in the slots 16 for abrading the wall of a cylinder. An expansion member 24 is axially slidable within the hone body to expand the honing elements into contact with the cylinder wall. 7

The honing elements 22 may be of several different 3,l95,282 Patented July 20, 1965 constructions, but in the present instance each comprises an elongated generally rectangular bonded abrasive stick 26 mounted in a casing 28. The casing 28 is of any suitable non-abrasive material which preferably wears at the same rate as the abrasive so as to wear away with the abrasive by contact with the wall of the cylinder but Without having any cutting or abrading action. Thus, for example, the casing may be formed of metal such as aluminum or magnesium, or of resinous plastic. The casing is in the form of an elongated shell which has substantially the same, although somewhat smaller, outline as the slot 16, as seen in FIGURES 2 and 3. The outer surface of the casing is notched from side to side to receive the stone 26 which may be secured in the notch in any manner such as by a suitable adhesive. The width of the stone is the same as that of the casing. The sides of the abrasive stick may remain exposed, or one or both sides can be covered with a suitable coating so as not to have an abrading action on the spring described hereinafter.

The bottom 30 of the casing of each honing element is inclined as shown in FIGURE 1 at the same inclination as the cone shaped end portion 32 of the expansion member 24. Hence, as the expansion member is moved to the left the honing elements are cammed radially outwardly, and as the expansion member 24 is moved to the right the honing elements may be retracted radially inwardly.

A flexible resilient leaf spring 34 lines each slot. The leaf spring 34 is an elongated member made of a suitable spring metal and it will be noted that the general outline of the honing element is smaller than the slot outline by an amount equal to the thickness of the leaf spring. One end of the leaf spring is substantially flush with an end 35 of the recess 19 and follows the slot contour in full surface-to-surface relation therewith around a major portion of the wall of the slot. The portion of the leaf spring between the ends of recess 19 is bonded to the slot wall in any suitable way such for example as by silver soldering, brazing or hydrogen brazing. The leaf spring has an end portion 36 which is not secured to the slot wall and is connected to the secured portion of the spring by an offset portion 38 which extends into and engages the bottom of the recess. The free end portion 36, in its normal free state or condition extends inward with respect to the slot at an angle from the olfset portion 38, as shown in FIGURE 2.

The abrasive element 22 is inserted lengthwise into the spring lined slot in the manner illustrated in FIGURE 2, and when fully inserted, as shown in FIGURE 3, the free end portion 36 of the spring is flexed outward by the side of the abrasive element. Hence the free end portion 36 of the spring has a yielding, resilient, friction contact with the side of the abrasive element, holding it in place within the slot. The free end portion 36 also presses the abrasive element against the opposite side of the spring to increase the friction contact and resistance to withdrawal. It will thus be seen in FIGURE 3 that the abrasive element is snugly received within the leaf spring and held in place frictionally by the spring action of the free end portion 36 thereof.

FIGURES 5 and 6 show a modification in which the spring has a slightly different outline and the slot 16 does not have a recess 19. The free end portion 36' of the leaf spring 34' is connected smoothly into the remainder of the spring, that is without the provision of an intermediate or connecting offset portion such as indicated at "38 in FIGURES 2 and 3. The portion of the leaf spring 34' shown contacting the wall of the slot in FIGURE 5 is secured thereto, in the same manner as in the embodiment of FIGURES 1 to 3. FIGURE 5 also illustrates v.3) the free or unstressed condition of the end portion 36' of the spring in which it inclines inward away from the slot wall. As shown in FIGURE'6, the free end portion 36' is cammed or flexed outward against the slot Wall when the abrasive element is inserted so as to have a resilient friction contact with the side of the abrasive element and thereby frictionally hold it in the slot. Otherwise the embodiment of FIGURES 5 and 6 is like that shown in FIGURES 1-4.

In both embodiments, it will be understood that the other slots, springs and abrasive elements in the hone bodies, which are spaced circumferentially from the ones shown, will be exactly like those illustrated and described.

In use, the honing elements are cammed radially outward by the expansion member 24 and the hone body is reciprocated and rotated in a bore to abrade the wall of the bore. When the tool is withdrawn from the bore, there is enough friction between the springs and honing elements to prevent the honing elements from being thrOWn out of the slots by centrifugal force.

The slot walls of present day honing tools will in time become worn by rubbing contact with the honing elements. Instead of throwing away these used tools because of the oversized slots, the slots can be milled out to accommodate the springs, and the springs bonded into place as described to closely and frictionally receive the abrasive elements. Thus those honing tools which in the past have been considered worn out and in need o-f'replacement, can be restored tofull use by milling out the slots and inserting springs. Also new tools can be designed with oversized slots to accommodate the springs, since the springs actually frictionally retain the honing elements better than the slots without springs, because of their resilient holding action.

What I claim as my invention is:

1. A honing tool having an elongated body provided with a longitudinally extending elongated outwardly opening radial slot, an elongated relatively narrow flat leaf spring disposed in. surface-to-surface engagement with the side and end walls of said slot,opposite ends of said leaf spring being spaced apart, an intermediate portion of said leaf spring being secured to a wall of said slot, one end portion of said leaf spring being free of said slot and disposed along one side Wall thereof, said free end portion of said leaf spring inclining inwardly within said slot away'frorn said one side wall thereof, a radially slidable elongated honing element within and extending lengthwise of said slot,- said honing element being upon the inner side of said flat leaf spring, one side of said honin element engaging and flexing outward toward said one side wall of said slot the free end portionaforesaid of said leaf spring, whereby said honing element is frictionally retained in said slot by the flexed end free portion aforesaid of said leaf spring. a

2. [The honing tool defined in claim 1, wherein said one side wall of said slot has a longitudinally extending recess therein, and the free endpor-tionof said leaf spring is connected to said :leaf spring by an integral offset portion thereof engaging the bottom Wall of said longitudinally extending recess and providing a'fulcrum about which said free end portion can flex to retain the honing element in said slot.

3. The honing tool defined in claim 1, wherein the free end portion of said leaf spring is flexed outward by said honing elementagainst a sidewall of said slot, and said honing element isfrictionally retained in said slot by the fiexed free end portion of said leaf spring.

References Cited by the Examiner UNITED STATES PATENTS 3,084,487 4/63 Engle 51-331 3,109,266 11/63 Engle 51-4843 LESTER M. SW'I'NGLE, Primary Examiner.

J. SPENCER OVERHOLS-ER, Examiner. 

1. A HONING TOOL HAVING AN ELONGATED BODY PROVIDED WITH A LONGITUDINALLY EXTENDING ELONGATED OUTWARDLY OPENING RADIAL SLOT, AN ELONGATED RELATIVELY NARROW FLAT LEAF SPRING DISPOSED IN SURFACE-TO-SURFACE ENGAGEMENT WITH THE SIDE AND END WALLS OF SAID SLOT, OPPOSITE ENDS OF SAID LEAF SPRING BEING SPACED APART, AN INTERMEDIATE PORTION OF SAID LEAF SPRING BEING SECURED TO A WALL OF SAID SLOT, ONE END PORTION OF SAID LEAF SPRING BEING FREE OF SAID SLOT AND DISPOSED ALONG ONE SIDE WALL THEREOF, SAID FREE END PORTION OF SAID LEAF SPRING INCLINING INWARDLY WITHIN SAID SLOT AWAY FROM SAID ONE SIDE WALL THEREOF, A RADIALLY SLIDABLE ELONGATED HONING ELEMENT WITHIN AND EXTENDING LENGTHWISE OF SAID SLOT, SAID HONING ELEMENT BEING UPON THE SIDE OF SAID FLAT LEAF SPRING, ONE SIDE OF SAID HONING ELEMENT ENGAGING AND FLEXING OUTWARD TOWARD SAID ONE SIDE WALL OF SAID SLOT THE FREE END PORTION AFORESAID OF SAID LEAF SPRING, WHEREBY SAID HONING ELEMENT IS FRICTIONALLY RETAINED IN SAID SLOT BY THE FLEXED END FREE PORTION AFORESAID OF SAID LEAF SPRING. 